The Obama administration's top lawyer told the Supreme Court on Tuesday that the health reforms Mitt Romney signed into law in Massachusetts helped inspire the president's controversial health care overhaul—that Romneycare shaped Obamacare.

With the law's fate in the balance, Solicitor General Donald Verrilli told the nine justices that the individual mandate—the requirement that people have health insurance or pay a penalty—was constitutional and slapped down other options such as requiring that individuals buy insurance when they go to get health care.

"That will never work. Congress understood that. It chose the means that will work, the means that it saw worked in the states, and in the state of Massachusetts, and that it had every reason to think would work on a national basis," Verrilli said as he wrapped up his arguments on the second of three days of Supreme Court hearings on the law.